WASHINGTON — The U.S. military recently came within inches of successfully retrieving three unmanned air vehicles in flight with a C-130 aircraft, bringing the Gremlins program tantalizingly close to a significant milestone.

The Defense Advanced Research Projects Agency, the Pentagon’s emerging technology arm, wants to demonstrate the ability to launch and recover four cheap, reusable unmanned aerial vehicles — the Gremlins — within 30 minutes in flight. The program uses X-61A Gremlins Air Vehicle (GAV) developed by Dynetics, a Leidos subsidiary. The GAVs are built to dock with a C-130 aircraft via an extension, similar to an airborne refueling operation.

Dynetics secured a 21-month, $38.6 million award for the third phase of the Gremlins effort in 2018.

While GAVs are relatively small, they have a range of more than 600 miles and can be equipped with a variety of sensors and technologies for different missions. The ability to distribute and collect GAVs from the air could keep them beyond the range of adversary defenses, according to DARPA, expanding the potential impact of unmanned aerial vehicles on the battlefield. Once recovered, GAVs are expected to be mission ready within 24 hours.

In the latest demonstration Oct. 28, DARPA made nine attempts to collect the GAVs with a docking mechanism extended from the C-130 aircraft. While none of the attempts was successful, with each GAV eventually parachuting to the ground, DARPA insisted the effort validated all autonomous formation flying positions and safety features.

“All of our systems looked good during the ground tests, but the flight test is where you truly find how things work,” said Scott Wierzbanowski, program manager for DARPA’s Gremlins effort, in a Dec. 10 statement. “We came within inches of connection on each attempt but, ultimately, it just wasn’t close enough to engage the recovery system.”

Given the GAVs’ performance and the data collected over the nine attempts, Wierzbanowski said success is imminent.

“We made great strides in learning and responding to technological challenges between each of the three test flight deployments to date,” he said. “We were so close this time that I am confident that multiple airborne recoveries will be made in the next deployment. However, as with all flight testing, there are always real-world uncertainties and challenges that have to be overcome.”

The next attempt will take place in spring 2021.

While the Gremlins effort is ongoing, the U.S. Army has made strides in its own effort to retrieve small drones midair. During a recent demonstration, the Army was able to snag air-launched effects (ALE) — effectively small drones — from the air using the flying launch and recovery system (FLAReS). FLAReS uses a hook to catch the ALEs by the wing in flight, saving them from the wear and tear of a belly landing on the ground.

Nathan Strout covers space, unmanned and intelligence systems for C4ISRNET.

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